This invention relates in general to vehicular body and frame assemblies. In particular, this invention relates to an apparatus and method for forming joints between various components, such as between side rails and cross members, in such a vehicle body and frame assembly.
Many land vehicles in common use, such as automobiles, vans, and trucks, include a body and frame assembly that is supported upon a plurality of groundengaging wheels by a resilient suspension system. The structures of known body and frame assemblies can be divided into two general categories, namely, separate and unitized. In a typical separate body and frame assembly, the structural components of the body portion and the frame portion are separate and independent from one another. When assembled, the frame portion of the assembly is resiliently supported upon the vehicle wheels by the suspension system and serves as a platform upon which the body portion of the assembly and other components of the vehicle can be mounted. Separate body and frame assemblies of this general type are found in most older vehicles, but remain in common use today for many relatively large or specialized use modern vehicles, such as large vans, sport utility vehicles, and trucks. In a typical unitized body and frame assembly, the structural components of the body portion and the frame portion are combined into an integral unit that is resiliently supported upon the vehicle wheels by the suspension system. Unitized body and frame assemblies of this general type are found in many relatively small modern vehicles, such as automobiles and minivans.
Each of these body and frame assemblies is composed of a plurality of individual vehicle frame components that are secured together. In the past, virtually all of these vehicle frame components have been manufactured from a metallic material. Steel has traditionally been the preferred material for manufacturing all of such vehicle frame components because of its relatively high strength, relatively low cost, and ease of manufacture. Vehicle frame components manufactured from traditional metallic materials have been secured together by conventional welding techniques. As is well known, conventional welding techniques involve the application of heat to localized areas of two metallic members, which results in a coalescence of the two metallic members. Such welding may or may not be performed with the application of pressure, and may or may not include the use of a filler metal. Although conventional welding techniques have functioned satisfactorily in the past, there are some drawbacks to the use thereof in joining metallic vehicle frame components together. First, as noted above, conventional welding techniques involve the application of heat to localized areas of the two metallic frame members. This application of heat can cause undesirable distortions and weaknesses to be introduced into the metallic components. Second, while conventional welding techniques are well suited for joining components that are formed from similar metallic materials, it has been found to be somewhat more difficult to adapt them for use in joining components formed from dissimilar metallic materials. Third, conventional welding techniques are not easily adapted for joining components that have different gauge thicknesses. Inasmuch as the production of vehicle frames is usually an high volume, low margin process, it would be desirable to provide an improved apparatus and method for permanently joining two or more metallic vehicle frame components that avoids the drawbacks of conventional welding techniques.